package apka.SMSBillet.DB;

import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;

import android.content.Context;
import android.database.Cursor;
import android.database.SQLException;
import android.database.sqlite.SQLiteDatabase;
import android.database.sqlite.SQLiteException;
import android.database.sqlite.SQLiteOpenHelper;

public class DataBaseHelper extends SQLiteOpenHelper{
	 //The Android's default system path of your application database.
    private static String DB_PATH = "/data/data/apka.SMSBillet/databases/";
    
    private static String DB_NAME = "zonerNT.sqlite3";
 
    private SQLiteDatabase myDataBase; 
 
    private final Context myContext;
 
    /**
     * Constructor
     * Takes and keeps a reference of the passed context in order to access to the application assets and resources.
     * @param context
     */
    public DataBaseHelper(Context context) {
 
    	super(context, DB_NAME, null, 1);
        this.myContext = context;
    }	
 
  /**
     * Creates a empty database on the system and rewrites it with your own database.
     * */
    public void createDataBase() throws IOException{
     	boolean dbExist = checkDataBase();
     	if(dbExist){
    		//do nothing - database already exist
    	}else{
    		//By calling this method and empty database will be created into the default system path
               //of your application so we are gonna be able to overwrite that database with our database.
        	this.getReadableDatabase();
        	try {
    			copyDataBase();
    		} catch (IOException e) {
 
        		throw new Error("Error copying database");
        	}
    	}
    }
 
    /**
     * Check if the database already exist to avoid re-copying the file each time you open the application.
     * @return true if it exists, false if it doesn't
     */
    private boolean checkDataBase(){
 
    	SQLiteDatabase checkDB = null;
    	try{
    		String myPath = DB_PATH + DB_NAME;
    		checkDB = SQLiteDatabase.openDatabase(myPath, null, SQLiteDatabase.OPEN_READONLY);
    	}catch(SQLiteException e){
 
    		//database doesn't exist yet.
    	}
 
    	if(checkDB != null){
    		checkDB.close();
    	}
 
    	return checkDB != null ? true : false;
    }
 
    /**
     * Copies your database from your local assets-folder to the just created empty database in the
     * system folder, from where it can be accessed and handled.
     * This is done by transfering bytestream.
     * */
    private void copyDataBase() throws IOException{
 
    	//Open your local db as the input stream
    	InputStream myInput = myContext.getAssets().open(DB_NAME);
 
    	// Path to the just created empty db
    	String outFileName = DB_PATH + DB_NAME;
 
    	//Open the empty db as the output stream
    	OutputStream myOutput = new FileOutputStream(outFileName);
 
    	//transfer bytes from the inputfile to the outputfile
    	byte[] buffer = new byte[1024];
    	int length;
    	while ((length = myInput.read(buffer))>0){
    		myOutput.write(buffer, 0, length);
    	}
 
    	//Close the streams
    	myOutput.flush();
    	myOutput.close();
    	myInput.close();
 
    }
 
    public void openDataBase() throws SQLException{
 
    	//Open the database
        String myPath = DB_PATH + DB_NAME;
    	myDataBase = SQLiteDatabase.openDatabase(myPath, null, SQLiteDatabase.OPEN_READONLY);
 
    }
 
    @Override
	public synchronized void close() {
 
    	    if(myDataBase != null)
    		    myDataBase.close();
 
    	    super.close();
 
	}
 
	@Override
	public void onCreate(SQLiteDatabase db) {
		
	}
 
	@Override
	public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
 
	}
	

    //---retrieves all the Cities---
    public Cursor getAllCities() {
        return myDataBase.query(
        		"city", 
        		new String[] {
		        				"name"}, 
                null, 
                null, 
                null, 
                null, 
                null);
    }
    
    //---retrieves city ID for the city.
    public Cursor getCityID(String city){
    	return myDataBase.rawQuery("SELECT cityInZone.zoneId " +
    			"From cityInZone " +
    			"INNER JOIN city " +
    			"ON city._id=cityInZone.cityId " +
    			"where city.name=?", 
    			new String[]{city} 
    			);
    }
    
    public Cursor getZonesBetween(int cityFrom, int cityTo){
    	return myDataBase.query(
    			"nordjylland", 
    			new String[]{
    					"_id",
    					"z"+cityFrom
    			},
    			"zone = "+cityTo,
    					null,
    					null, 
    					null, 
    					null);
    }
    
//    select "z"+fromCity 
//    from nordjylland 
//    where zone = toCity

//    //---retrieves a particular title---
//    public Cursor getTitle(long rowId) throws SQLException 
//    {
//        Cursor mCursor =
//                db.query(true, DATABASE_TABLE, new String[] {
//                		KEY_ROWID,
//                		KEY_ISBN, 
//                		KEY_TITLE,
//                		KEY_PUBLISHER
//                		}, 
//                		KEY_ROWID + "=" + rowId, 
//                		null,
//                		null, 
//                		null, 
//                		null, 
//                		null);
//        if (mCursor != null) {
//            mCursor.moveToFirst();
//        }
//        return mCursor;
//    }
	
       // Add your public helper methods to access and get content from the database.
       // You could return cursors by doing "return myDataBase.query(....)" so it'd be easy
       // to you to create adapters for your views.
 
}


